1. Department of Biological Engineering, Massachusetts Institute of Technology (MIT), Cambridge, Massachusetts 02139, USA;
2. Institute for Medical Engineering and Science, MIT, Cambridge, Massachusetts 02139, USA
3. Wyss Institute for Biologically Inspired Engineering, Harvard University, Boston, Massachusetts 02115, USA
4. Microbiology Graduate Program, MIT, Cambridge, Massachusetts 02139, USA
5. Synthetic Biology Center, MIT, Cambridge, Massachusetts 02139, USA
6. Broad Institute of MIT and Harvard, Cambridge, Massachusetts 02142, USA